A seed is a tiny plant embryo with a protective shell. It contains a food supply called endosperm and the beginnings of leaves, stems and roots.
A seed must find the right conditions to grow. These include a good soil, plenty of water and sunlight.
What is a seed?
A seed is the part of a plant that grows into a new plant. It is a small, hard, and delicate structure that contains the embryo of the original plant.
A seed contains three parts: the embryo, the endosperm, and the seed coat. The endosperm stores food to nourish the new plant as it begins to grow.
The seed also contains the cotyledon, which is a type of leaf that grows inside the seed. The cotyledon absorbs nutrients from the endosperm and transfers them to the embryo.
In monocotyledonous plants, the seed has additional structures such as a pericarp, scutellum (single large cotyledon), plumule (prospective shoot), radicle, and hypocotyl. The hypocotyl acts as a rudimentary axis that connects the radicle and plumule.
How do seeds grow?
A seed is a small plant that contains all the information needed for its growth and development. However, not all seeds are created equal.
A plant’s seed consists of an embryo, endosperm, and seed coat. During germination, the seed needs water and nutrients to grow.
Water is absorbed through a tiny opening in the seed coat and causes swelling. This reactivates the storage compounds in the seed, allowing them to become available for the growing embryo.
Once the seed has absorbed enough water, enzymes in the endosperm break down the storage compounds into sugars. This initiates metabolic processes in the seed that begin to divide the cells and create an embryo.
Seeds can remain viable for weeks, months, or even years. This longevity is due to the fact that they have a variety of specialized features for dispersal, such as plumes for wind dispersal or hooks, barbs, or sticky hairs that attach to fur or feathers.
What are the different types of seeds?
There are a variety of different types of seeds. Some are used for food, while others are used for plant breeding or landscaping.
Some common types of seeds include grain, legume, and nut seed. They are a valuable source of nutrition for both humans and animals.
They can be eaten whole, ground into flour, or used to make oil. They are also a source of protein and antioxidants.
There are three main types of seeds based on how they were grown or bred: open-pollinated, hybrid, and GMO (genetically modified organism). Be careful when reading labels.
How do seeds germinate?
Seeds need the right temperature, moisture, air and light conditions to germinate. This is often controlled by the seed’s environment and species.
Most seeds require temperatures between 25deg-30degC to germinate successfully. Anything below or above this can damage the seed and make it go into dormancy (see Table 1).
Water imbibition is the process of the seed absorbing water from its environment. This causes the cells inside the seed to swell and expand.
This expansion releases energy from its food reserve for growth.
Respiration takes place as the seed absorbs oxygen to carry out cellular processes, such as digestion of stored starch and protein.
Finally, light exposure triggers the sprouting of a root and shoot. This allows the plant to grow and photosynthesize.